Plans to connect U.S. Highway 550 to a $47 million interchange that includes the so-called “Bridge to Nowhere” have been delayed again while an engineering firm considers yet another proposal for realigning the highway.

The Colorado Department of Transportation said it will evaluate a new proposal submitted by the Webb family, which owns a ranch that CDOT needs to cross to connect Highway 550 to the Bridge to Nowhere and U.S. Highway 160.

The Webb’s proposal would use the existing Farmington Hill alignment rather than the Bridge to Nowhere, said Nancy Shanks, spokeswoman for CDOT.

It would include modifications to allow for higher speeds and greater safety, she said. It would impact part of the Webb Ranch, and would likely require the full acquisition of two residential properties and one business, Eagle Block, which sells masonry and landscaping supplies.

An engineering firm is still working on the final details of the Webb proposal.

“It looks like this proposal could meet project purpose and need,” Shanks said, “but because it hasn’t been designed fully, that has not been determined yet.”

“Purpose and need” is the threshold a proposal must meet to be formally considered.

An independent engineering firm will determine if the proposed connection meets federal safety and environmental requirements, and, if so, the proposal will be evaluated against all the other “reasonable alternatives” that have been previously considered, Shanks said.

CDOT announced plans in July to realign Highway 550 across the Webbs’ historic ranch and connect it with the Bridge to Nowhere.

The agency expected to receive a formal “record of decision” – the final blessing from the Federal Highway Administration – about now, Shanks said.

But because the Webb family submitted a new proposal that appears to meet federal requirements, the agency must consider it, Shanks said.

“It could take up to two years from now to reach a record of decision,” she said.

CDOT received a formal record of decision in 2006 to cross the Webb ranch, but the decision had to be revisited to account for a gas well on the ranch and the ranch’s historic designation – factors that were not previously considered.

The Federal Highway Administration approved construction of the interchange in 2008 regardless of whether Highway 550 would ever connect with the bridge, saying the interchange had “independent utility.”

CDOT has since completed construction of the $47 million interchange. It includes a roundabout, a partial footpath, four bridges (including two that span Highway 160), six retaining walls, and on- and off-ramps.

But without a connection to Highway 550, the interchange receives little use. Earlier this year, The Durango Herald counted 14 vehicles that used the interchange during a one-hour period, from 3 to 4 p.m. on a weekday.

CDOT projected traffic volume through the Grandview corridor to double from 19,200 vehicle trips per day in 2000 to 42,500 trips per day by 2025, not including new development in Grandview. Traffic did increase to 25,600 trips per day in 2008 – the start of the Great Recession – but it has since decreased to 22,000 trips per day in 2011.

CDOT’s proposal to cross the Webb Ranch would cost an estimated $77.6 million and require the excavation of 1.6 million cubic yards of dirt to make the connection to the Bridge to Nowhere.

By comparison, the Webbs’ proposal would cost an estimated $116 million and require the same amount of excavation, according to numbers provided by the Webbs.

The Webbs have submitted several proposals in the past for realigning Highway 550 – all of which would use the existing Farmington Hill – but none of them met federal safety requirements, and, therefore, didn’t go through a complete evaluation, Shanks said.

CDOT expects to spend up to $2 million evaluating the Webb’s newest proposal.